When dealing with explosive ordnance it is important that precautions have been taken to assure that the ordinance is incapable of being accidentally exploded in high temperature environments. Warhead cook-off is the response of the explosive warhead to excessive thermal environments such as a fire or abnormally high temperatures. Cook-off is an undesirable reaction of the explosive which typically starts as a burning or deflagration process, but can continue into a detonation process if the explosive remains confined. The detonation of a warhead under such circumstances can cause severe property damage and loss of life. Thus, restricting cook-off reactions to merely burning of the warhead material will substantially improve the safety aspects of the warhead. For example, a number of prior art cook-off preventions include using casings of reinforced plastic which soften and fail on direct cook-off due to exposure to flame before the contained material attains cook-off temperature. However, this arrangement is ineffective when the casing is subjected to slow cook-off from indirect heating.
Other types of ammunition casings, formed from hardened materials, e.g. stainless steel, have met many of the needs of modern warfare, while failing to meet others. The choice of stainless steel, for example, has yielded casings which have a great deal of strength and have been able to withstand the rigors of combat. The main disadvantage of stainless steel casings, however, has been the reaction of the encased ammunition to heat. When the hardened shell has a melting point higher than the ignition temperature of the enclosed ammunition, the shell or casing contains the expanding gases created during the ammunition cook-off. When the pressure of these expanding gases is great enough, the casing ruptures generating damage and metal fragments. The prior art has addressed the problem of munition cook-off. For example, U.S. Pat. No. 4,991,513 describes means for providing vent holes in the munition casing using a mechanism to open or close the holes. U.S. Pat. No. 5,361,703 discloses a casing, which contains the charge, with an arrangement for opening the casing to vent the pressure before the casing attains a temperature where cook-off may occur. These prior technologies, however, have resulted in disadvantages such as increased weight, poor sealing of the casing, increased complexity requiring operator action to ready the munition, increased cost and various other disadvantages. In accordance with this invention, however, a carbon fiber composite munition casing is provided which has increased strength, lower weight, and lower cost, while retaining the insensitive characteristics when subjected to higher temperatures.